Dioxins are a group of chemicals that may be encountered as environmental pollutants. These chemicals can persist for prolonged periods in both nature and exposed animals.
Dioxins include: polyhalogenated dibenzo-p-dioxins, dibenzofurans, biphenyls, naphthalenes, azo-benzenes and azocy-benzenes
2,3,7,8-tetrachlordibenzo-p-dioxin (TCCD) is a common dioxin that is relatively toxic. It is often used as a reference against which other dioxins are compared.
The dioxins are lipophilic and can accumulate in adipose tissue. They bind to the aryl hydrocarbon receptor (AhR) which is a transcription factor and nuclear receptor.
4 lateral halogens are necessary to achieve "dioxin-like" effects with increasing halogenation associated with decreased toxicity (Birnbaum).
Sources: combustion, byproduct of industrial processes, herbicide (Agent Orange)
Clinical effects:
(1) chloracne (cystic acne with altered pigmentation and hyperkeratosis)
(2) hepatitis with elevated liver function tests
(3) atrophy of lymphoid tissue with immune defects
(4) headaches
(5) malaise
(6) sensory changes
(7) cardiac toxicity
(8) wasting syndrome (severe loss of body mass)
(9) carcinogenic
(10) teratogenic
